Re: [PATCH 2/8] qio: Minor optimization when callback function is unchanged

[Kevin Wolf <kwolf@redhat.com>]

Am 03.11.2025 um 21:10 hat Eric Blake geschrieben:
> In qemu-nbd and other NBD server setups where parallel clients are
> supported, it is common that the caller will re-register the same
> callback function as long as it has not reached its limit on
> simultaneous clients.  In that case, there is no need to tear down and
> reinstall GSource watches in the GMainContext.
> 
> Signed-off-by: Eric Blake <eblake@redhat.com>
> ---
>  io/net-listener.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/io/net-listener.c b/io/net-listener.c
> index 0adbc409cf2..e89286ea63c 100644
> --- a/io/net-listener.c
> +++ b/io/net-listener.c
> @@ -147,6 +147,10 @@ void qio_net_listener_set_client_func_full(QIONetListener *listener,
>  {
>      size_t i;
> 
> +    if (listener->io_func == func && listener->io_data == data) {
> +        return;
> +    }

Wouldn't a change of listener->io_notify also be significant?

Kevin